• KSBB Journal
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• v.22 no.5
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• pp.366-369
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• 2007

In this study, the feasibility of reusing the eluent was confirmed by monitoring its specific gravity during the chromatographic purification of paclitaxel from plant cell cultures. The specific gravity of the eluent (methanol/water = 70/30, v/v) was measured prior to its elution through the hydrophobic resin column. The measurement showed a specific gravity of 0.853. The discharged eluent from the column outlet was first evaporated under vacuum pressure. The evaporated eluent was collected and condensed into a liquid eluent again, followed by the HPLC analysis in order to check the presence of any trace of impurity. Even if the specific gravity of the liquid eluent is varied from 0.853 as a result of the evaporation and condensation, the eluent can still be reused after it specific gravity is adjusted by the addition of methanol or water. The reuse of the eluent resulted in the paclitaxel yield of 86% with a purity of 95% which were closely similar to those of before the eluent reuse. These results indicate that the strategy of reusing the eluent on the basis of the specific gravity analysis was successfully implemented in this study.

• Journal of the Korean Chemical Society
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• v.38 no.9
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• pp.660-666
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• 1994

The effects of temperature and flow rate of eluent on the separation of adjacent lighter lanthanide pairs (La : Ce, Ce : Pr, Pr: Nd) have been studied with displacement chromatography. Two serial columns packed with Amberlite 120 cation exchange resin are used for loading and separation. The retaining ion is $H^+$ ion and the eluent is 0.012M and 0.015M of EDTA solution. The columns and the eluent are maintained at the temperature of 90$^{\circ}C$ and pressurized to reduce vaporizing in the ion-exchange resin column. The eluated solution is analyzed directly with ICP-AES. The separation factors of the lanthanide pairs, La: Ce, Ce :Pr, and Pr: Nd, are 4.6, 2.8, and 1.9, respectively and are higher than that from theoretical calculation at 25$^{\circ}C$. When the flow rate is reduced from 2.5 ml/min to 1.5 ml/min, the HETP is reduced from 1.60 cm to 0.88 cm. The separation efficency can be improved at lower flow rate of eluent and higher operating temperature. The recoveries of pure lanthanides than 99.9% are 49∼77% from this separation.

• The Journal of the Petrological Society of Korea
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• v.24 no.4
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• pp.365-371
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• 2015

The rare earth element(REE)s play an important role in understanding of rock formation and evolution because of their similar geochemical behaviors. Sm and Nd are more useful than other REEs because Sm-Nd isotopic system has important applications for geochemical interpretation like age dating and crustal evolution. These studies require a chromatographic technique for Sm and Nd separation from the geological samples. Ln-resin method using 0.25 M HCl as the eluent is widely used for Nd separation. However, this technique has a disadvantage of the poor elemental selectivity that the Nd fraction contains Ce as a tailing of the previous fraction. This technical report is a comparison study on the effect of eluent concentration between 0.25 M HCl and 0.15 M HCl on the separation of Nd with Ln-resin method for improving the technique of Nd separation. The results showed that the separation of Ce and Nd using 0.15M HCl as the eluent was not effective compared to the separation using 0.25 M HCl. In this experiment, we could confirm that the dilution of eluent might not be effective on the high purity separation of Nd with Ln-resin method.

• Journal of the Korean Chemical Society
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• v.11 no.2
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• pp.56-59
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• 1967

Mixtures of amines can be separated by elution chromatography on a chelating resin, Dowex A-1 loaded with nickel ions based on ligand exchange. Aqueous ammonia is used as the eluent. The method has proved particulary effective for separating aromatic amines.

• Journal of the Korean Chemical Society
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• v.36 no.5
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• pp.692-696
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• 1992

$NH_4^+ form cation exchange resin was used to separate one rare earth element from the rare earth mixture solution using Ln-EDTA eluent. Rare earth mixture solution was passed through the resin bed and eluted with 0.1M La-EDTA solution as an eluent. In here all the rare earth element except lanthanum ion are eluted and lanthanum ion absorbed in resin bed is eluted using 0.1M EDTA solution. If Ce-EDTA solution instead of La-EDTA solution was used as an eluent, all the rare earth element except cerium ion are eluted and cerium ion is eluted with 0.1M EDTA solution. This method can be applied to separate the individual rare earth element from the mixture. The separation mechanism is as follows: Absorption : 3RNH_4 ＋ Ln^{3+} = R_3Ln ＋ 3NH_4^+, La-EDTA elution : R_3Ln ＋ La-Y- = R_3La ＋ Ln-Y-, EDTA elution : R_3La ＋ HY^3- = La_-Y ＋ RH ＋ 2R^-.$

• Membrane Journal
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• v.8 no.1
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• pp.50-58
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• 1998

Protein affinity membranes were prepared via coating of chitosan gel on the porous flat and hollow-fiber polysulfone membranes, followed by the immobilization of the reactive dye (Cibacron Blue 3GA) to the chitosan gel. Maximum protein binding capacity of these affinity membranes was about 70 $\mu{g/cm}^2$. Using the affinity flat membrane module, the elution chromatography of human serum albumin (HSA) was performed to determine the optimum condition of eluent buffer. The optimum condition of eluent was the universal buffer solution of 0.06 M concentration containing 1 M KCl at pH 10. For the frontal chromatography of HSA using the flat module, the dynamic protein binding capacity was rapidly decreased from the equilibrium values with increasing flow rate and HSA concentration of the loading solution. However, in the case of hollow-fiber module, the dynamic binding capacity was maintained an equilibrium value without depending on the operating conditions. These results showed that the hollow-fiber module was more effective than the flat module as an affinity chromatography column.

• YAKHAK HOEJI
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• v.34 no.3
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• pp.215-218
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• 1990

An ion chromatographic method based on indirect photometric detection of UV transparent anions was developed. Separation of anion was accomplished on strong anion exchange column (Waters SAX) using UV detector at 254 nm. Among examined UV-active additives (Dns-H, Dns-glu, Dnsser, Dns-val), Dns-glu showed the highest sensitivity. Studies on the effects of the pH and ionic strength of eluent revealed that the increase of pH and ionic strength of the eluent decreased capacity factor. The best eluent for the separation of acetate, fluoride, chloride, nitrate and bromide was $1\;{\times}\;10^{-4}M$ Dns-glu in 5 mM phosphate buffer (pH 6.30). The detection limit of chloride ion was 2.1 ng in this condition.

• Journal of the Korean Chemical Society
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• v.15 no.2
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• pp.45-48
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• 1971

The various eluents have been used for the separations of alkaline earth metals by elutions through cation exchange resin column by many investigators. We find, the mixed solution of 1M HAc and 1M NaAc (pH 4.75) is the best eluent for this purpose, becouse the one step elution through 7cm Dowex 50w${\times}$8(100~200mesh) resin column with this eluent, gives the quantitative separation. When 2M NaAc is used as a eluent Sr(II) and Ba(II) is separated easily without any contamination of Mg(II) andCa(II). The Ca-Pb alloy which is composed of Cu, Ca, Sr, Ba and abundance of Pb metal is separated quantitatively into its components by the two step elution with 0.3M HAc + 0.3M NaAc(PH 4.75) and 0.5M HAc + 0.5M NaAc(PH 4.75) as eluents through 10cm resin column.

• Archives of Pharmacal Research
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• v.9 no.4
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• pp.211-214
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• 1986

A simultaneous determination method of alkaline earth metals was attempted with the conventional high performance liquid chromatographic system. Four cations, namely, magnesium, calcium, strontium and barium ion, were injected directly as aqueous solution into an eluent containing copper chloride solution and and were successfully separated and determined on a separating column (Zipax SCX, 4.6 mm i.d. ${\times}25$ cm length, Du Pont, USA) by using a variable wavelength UV detector. The linear calibration curves were obtianed in the range from $1.0{\times}10^{-4}M$ to $5.0{\times}10^{-4}M$ and the correlation coefficient of the calibration curve for each metal of magnesium and calcium in tap water. Alkaline earth metals were determined with the conventional high performance liquid chromatographic system.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2651-2656
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• 2012

Sulfonated cellulose tris(3,5-dimethylphenylcarbamate) (SCDMPC)-coated zirconia monolith (ZM) was used as the chiral stationary phase in capillary electrochromatography for separation of enantiomers of ten chiral compounds in acetonitrile (ACN)-phosphate buffer mixtures as the eluent. Influences of the ACN content, buffer concentration and pH on chiral separation have been investigated. Separation data on SCDMPC-ZM have been compared with those on CDMPC-ZM. Resolution factors were better on SCDMPC-ZM than CDMPC-ZM while retention factors were in general shorter on the former than the latter. Best chiral resolutions on SCDMPC-ZM were obtained with the eluent of 50% ACN containing 50 mM phosphate at pH around 4.